The presentation of the images took place at an event called Be Witness at the National Auditorium in Mexico City, which seats 10,000 people, on Tuesday (5 May). The programme was hosted by Jaime Maussan, the host of the television show, Tercer Milenio, which focuses on UFOs among other topics. The topic, of course, is a controversial one, and official bodies such as Nasa in the United States have never formally recognised alien life on planet Earth.

Geologist Bernard A Ray reportedly took the presented photos between 1947 and 1949 on a Kodachrome film that show the remains of a purported alien found dead in New Mexico. In 1947, the crash of an aircraft in Roswell, New Mexico, led to suspicions of alien involvement on planet Earth.

The photos were found inside a box, along with images of Bing Crosby, Clarke Gable and Dwight Eisenhower from before his term as president. The box was located in an attic of a house in Sedona, Arizona.

It took five years of research to confirm the authenticity of the latest images, UFO specialists claim. And according to Maussan, a widely recognised Mexican UFO specialist, the images provide "undeniable" evidence that aliens do in fact exist.

Maussan claims these images must be real because the sketch of the extraterrestrial image did not exist at the time the photo was taken therefore making it impossible for these images to have been doctored in accordance with any models.

"(These photos) show the human race, beyond any doubt, that extraterrestrial visits are a reality. That is why the presentation of two slides, two transparencies, where a being with non-human features can be seen, is very important, especially if these photos were dated by experts during a period, where the model of the archetype extraterrestrial we know today did not exist, but also because it was also impossible to doctor these type of images in such a way," Maussan said.

Leading US researcher and writer on the subject of UFOs, Richard Dolan, further argued for the authenticity of the images.

"The analysis of the body or creature that is presented in the image, suggested that this is not a mummy, not a human, not a mammal and not a model, which would require a highly sophisticated detailed understanding of comparative anatomy among various species," Dolan said.

Edgar Mitchell, an astronaut who was the sixth person to land on the moon, attended the event, and was accompanied by a team of extraterrestrial investigators. They all claim the images are authentic and had not doctored. UFO enthusiasts who were unable to attend the event followed the revelations via internet streaming.